A plurality of luminaires using conventional incandescent lamps or energy saving lamps as light sources are known in the prior art. To save even more energy conventional luminaires are partially also provided with LEDs that have special optical attachments. The optical attachments are required to obtain a radiation characteristic similar to that of conventional illuminants. However, a compatible LED replacement illuminant is not available for all fields of application. Moreover, the production and development thereof are cost-efficient. It is, therefore, desirable to develop luminaires specifically for the use of LEDs.
A luminaire of the above-described type is known, for example, from DE 38 12 764 A1. The reflector of this luminaire includes several slots through which a portion of the light of a halogen lamp is passed to a sheet of transparent plastic which guides the light to the outside and emits it in a radial direction for decorative illumination purposes.
The disadvantage of the luminaire known from DE 38 12 764 A1 is that the slots in the reflector render the light emitted by the reflector non-uniform. Also, the light passed through the slots is not effectively coupled into the transparent plastic sheet. And it is not suited for the use of a simple LED as this would require an LED replacement illuminant compatible with the shape and holder of the halogen lamp.
A luminaire of the above-described type is known, for example, from DE 101 16 040 A1. In this luminaire a two-filament halogen lamp is used, the lamp being arranged such that one coil is arranged inside the reflector. The second coil is arranged outside the reflector, in front of the light entrance aperture, and thus illuminates the luminaire shade.
The disadvantage of the luminaire known from DE 101 16 040 A1 is that the use of a two-filament halogen lamp, respectively, two light sources is an obstacle to a compact design of the luminaire. In addition, it is not suited for the use of an LED.